Especially in the light of Zuckerberg's recent behaviour, please consider using Signal, it's actually good and a pretty easy replacement for Whatsapp

https://signal.org

Signal Messenger: Speak Freely

Say "hello" to a different messaging experience. An unexpected focus on privacy, combined with all of the features you expect.

Signal Messenger

@joelanman

Or https://element.io/
there are alternatives! Spread them (:

Element | Secure collaboration and messaging

Element is a Matrix-based end-to-end encrypted messenger and secure collaboration app. It’s decentralised for digital sovereign self-hosting, or through a hosting service such as Element Matrix Services. Element operates on the open Matrix network to provide interoperability and easy connections.